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Expanding plant genome-editing scope by an engineered iSpyMacCas9 system that targets A-rich PAM sequences.

ABSTRACT: The most popular CRISPR-SpCas9 system recognizes canonical NGG protospacer adjacent motifs (PAMs). Previously engineered SpCas9 variants, such as Cas9-NG, favor G-rich PAMs in genome editing. In this manuscript, we describe a new plant genome-editing system based on a hybrid iSpyMacCas9 platform that allows for targeted mutagenesis, C to T base editing, and A to G base editing at A-rich PAMs. This study fills a major technology gap in the CRISPR-Cas9 system for editing NAAR PAMs in plants, which greatly expands the targeting scope of CRISPR-Cas9. Finally, our vector systems are fully compatible with Gateway cloning and will work with all existing single-guide RNA expression systems, facilitating easy adoption of the systems by others. We anticipate that more tools, such as prime editing, homology-directed repair, CRISPR interference, and CRISPR activation, will be further developed based on our promising iSpyMacCas9 platform.

SUBMITTER: Sretenovic S

PROVIDER: S-EPMC8060698 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Expanding the Scope of Bacterial CRISPR Activation with PAM-flexible dCas9 Variants

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2022-11-15 | GSE217559 | GEO

Expanding the Scope of Bacterial CRISPR Activation with PAM-Flexible dCas9 Variants.

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SpRY greatly expands the genome editing scope in rice with highly flexible PAM recognition.

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